ETOPS:Expansion in the North Pacific Market

For nearly 14 years, operators around the world have successfully conducted extended-range twin-engine operations (ETOPS) with commercial airplanes. Even though twinjets are used globally on ETOPS routes, they dominate traffic in the North Atlantic market in particular. Recently, some U.S. and Asian operators have shown increased interest in using twinjets in the North Pacific market, where several operators plan to introduce the 777. Changes in air service agreements between nations, open-skies policies, and the availability of economically efficient twinjets may open additional point-to-point operations between cities in North America and Asia. Within a decade, these changes may also lead to ETOPS growth in the North Pacific market that could mirror the current level of activity in the North Atlantic.

Flight under extended-range twin-engine operations (ETOPS) rules has proven to be routine, safe, and highly successful around the world. ETOPS allows two-engine-airplane operation for up to 180 min from an en route alternate airport. ETOPS has been used successfully on airplanes built by all major airframe manufacturers, including Boeing (737, 757, 767, 777, and MD-80). The 767 is the most widely used airplane for ETOPS, and the world fleet of 767s has just completed its one millionth ETOPS flight. Though twinjets fly ETOPS routes around the world, they dominate in the North Atlantic market and show potential for the same success in the North Pacific ETOPS market.

Understanding ETOPS expansion includes a review of the following:

  1. ETOPS success
  2. History of ETOPS in the North Atlantic market
  3. Potential operations in the North Pacific market
  4. Availability of en route alternate airports
  5. Boeing support of ETOPS
ETOPS Success
Boeing twinjets complete about 600 ETOPS flights a day around the world (figure 1), for a total of more than 18,000 such flights each month and almost 1.25 million flights since 1985. Operators, regulatory authorities, and manufacturers have worked together to achieve a rate of in-flight shutdowns that is well below the target set byregulatory authorities. In addition, the excellent propulsion-related safety record of the twinjets has not only been maintained but potentially enhanced by the process-related provisions associated with ETOPS-type design and operational approvals. Some operators have adopted these ETOPS processes into their three- and four-engine airplane fleets and recorded notable improvements in overall reliability.

History of ETOPS in theNorth Atlantic Market
The number of ETOPS flights between North America and Europe has increased dramatically since 1985, when twin-engine operations across the North Atlantic were virtually nonexistent (figure 2). By 1990, however, U.S. operators were conducting more North Atlantic flight segments with two-engine airplanes than with three- and four-engine airplanes combined. This dramatic change occurred because efficient twinjets with the required range and seating capacities were introduced and because the ETOPS concept was approved, permitting operators to fly these twinjets on the most optimum routes across the North Atlantic.

Airplane availability affects operators' strategies and the type of service they provide. In the early 1970s, operators had few airplane choices to serve long-range routes between the United States and Europe. Economically efficient twinjets such as the 757 and 767, which had the range for such routes, came onto the market in the early 1980s. With the advent of ETOPS in 1985, operators could use these twinjets efficiently across the North Atlantic. By adding these long-range airplanes with fewer seats, operators offered the traveling public more choices between existing city pairs by increasing the number of flights and providing a wider variety of departure times. Additionally, operators began to add more new city pairs between Europe and North America. ETOPS made it possible for this new generation of airplanes to use its inherent range capabilities to reshape the North Atlantic market.

Potential Operations in theNorth Pacific Market
The United States and Japan recently signed a bilateral agreement that allows a 50 percent increase in the route frequencies established between the two nations in August 1997. Open-skies agreements, which allow operators in two consenting nations to freely introduce service between any two cities in each country, have already been established between the United States and Brunei, Malaysia, New Zealand, Singapore, South Korea, Taiwan, and Thailand. The resulting relaxation or complete removal of limits on the number of flights between Pacific Rim nations will likely allow operators to introduce airplanes with fewer seats, increase the flight frequency between existing city pairs, and inaugurate new city pairs. The availability of the 767 and 777 gives operators the opportunity to match the appropriate airplane to the demands of the North Pacific market. Several North American and Asian operators, including Air Canada, Asiana Airlines, Canadian Airlines International, China Southern Airlines, and United Parcel Service, have operated or are currently operating twinjets on these ETOPS routes in the North Pacific.

Availability of En RoutAlternate Airports
Planning for ETOPS requires operators to select en route alternate airports. According to the U.S. Federal Aviation Administration (FAA) Advisory Circular 120-42A on ETOPS, "These suitable en route alternates serve a different purpose than the destination alternate airport and would normally be used only in the event of an engine failure or loss of primary airplane systems."

Boeing data as of December 31, 1997, show that on average, an engine failure in the ETOPS portion of the flight causes one diversion to an ETOPS en route alternate for every 70,000 flights.

Though the focus on en route alternate airports is primarily for twinjets, these airports are important for the safety of all long-range operations regardless of the number of engines. A sufficient number of these airports must be available to support unscheduled landings due to such emergencies as cargo fire, decompression, fuel leak, passenger illness, or severe turbulence. Boeing data show that on several occasions, 747s and DC-10s have diverted to various islands in the Pacific, namely Adak, Midway, Shemya, and Wake. Reasons for these diversions included passenger or crew medical emergency, an unanticipated headwind requiring additional fuel, and a 747 diversion to Wake for an engine fire warning.

ETOPS rules require operators to ensure availability of en route alternate airports. However, data collected worldwide (figure 3) show that a four-engine airplane has as much, if not greater, need for diversion to such airports for engine-related causes. Ensuring the availability of en route alternates is a sound operational practice for all airplanes.

The North Pacific has several en route alternate airports (figure 4) that meet the ETOPS requirements for air traffic control, approach navigational aids, emergency services, runway load-bearing capacity and length, and weather reporting to successfully plan ETOPS flights. Boeing data indicate that most of these airports meet the requirements to support a wide variety of airplanes, including the 777.

Depending on the type of airframe/engine combination and the ETOPS single-engine speed, operations under 180-min ETOPS may be possible between the United States and Japan just using Anchorage, Alaska, in the United States, and Kushiro, Japan, as ETOPS en route alternates. However, for some airframe/engine combinations and the single-engine speed selected, one more en route alternate may be needed between Anchorage and Kushiro to operate under 180-min ETOPS or provide additional flexibility in routing (figure 5).

Prior to dispatch of an ETOPS flight, operators must ensure that the weather at the selected alternate airport meets the ETOPS weather minimums (a certain level of ceiling and visibility minimums). Boeing studied the weather data from 1985 through 1994 at alternate airports such as Magadan, Petropavlovsk, in Russia, and several airports in Alaska. Results of the study showed the probability of simultaneous airport closure as almost zero. The analysis showed that at least one airport will always be available between Anchorage and Kushiro. Several other adequate airports for ETOPS exist in the mid-Pacific, including Guam, Majuro, Midway, Saipan, and Wake. Data indicate that these airports will be available as en route alternates for the foreseeable future. These airports can be used as en route alternates for both North and Mid-Pacific operations. Operators and pilots in command will gain additional flexibility if the FAA and Joint Aviation Authorities approve a 15 percent operational extension of the current 180-min rule, as discussed in "Anticipated ETOPS Developments."

Boeing Support of ETOPS
The Boeing commitment to providing world-class customer service extends to ETOPS planning and approval support. Boeing is prepared to share with operators the data it has collected on North Pacific airports as well as route analyses.

The introduction of twinjets reshaped the North Atlantic market, and operators further expanded service to major transportation centers when economically efficient long-range twinjets entered service and ETOPS was approved. Travel between smaller city pairs in Europe and North America also benefited through increased point-to-point services. International air service agreements such as open-skies and the bilateral agreement between Japan, other Asian nations, and the United States are expected to increase flight frequencies in the North Pacific market. These agreements, combined with the availability of economically efficient, long-range airplanes such as the 777, may fuel the growth of ETOPS in the North Pacific to the current level of activity in the North Atlantic. Several airports in the North Pacific are equipped to meet ETOPS planning requirements and so serve as en route alternates for twinjets as well as for three- and four-engine long-range airplanes.

ETOPS History
In 1953, the United States developed regulations that prohibited two- and three-engine airplanes from routes more than 60 min from an adequate airport (single-engine flying time), unless approved by the U.S. Federal Aviation Administration (FAA). Known as the "60-minute rule," this restriction was based mainly on the reliability of piston engines used on airplanes in the 1940s and early 1950s. A recommendation by the International Civil Aviation Organization, also in effect since 1953, restricted the use of two-engine airplanes to routes 90 min from an adequate airport (all-engine flying time). In 1964, the FAA removed the 60-min restriction on three-engine airplanes.

By the 1970s, advances in engine technology yielded a tenfold reliability improvement over early piston engines. In 1983, the new generation of twinjets powered by high-bypass turbofan engines became the subject of extensive discussions involving international aviation regulatory authorities, airframe and engine manufacturers, and pilot and passenger associations. The discussions focused on the suitability of these twinjets to fly ETOPS and culminated in 1985 with the release of new requirements for obtaining FAA approval to operate twinjets beyond the 60-min rule. The new requirements permitted operators to seek approval for routes up to 120 min from an adequate airport (single-engine flying time), and were published in FAA Advisory Circular 120-42.

In 1988, after three years of successful ETOPS experience, the Advisory Circular was modified to include provisions for up to 180-min ETOPS. Aviation authorities in France, the United Kingdom, and several other countries also revised their regulations to incorporate similar provisions. In addition, Information Leaflet 20 published by the European Joint Aviation Authorities (JAA) provides for 180-min ETOPS.

A successful record of ETOPS operations has proven that the world's airframe manufacturers can design, build, and test airplanes suitable for such operations, and that operators can successfully maintain and fly them on ETOPS routes. In 1995, following nearly 10 years of successful ETOPS, the FAA and JAA accepted the Accelerated ETOPS Operational Approval method. This allows new twinjets to fly ETOPS routes from the first day of revenue operations and has been used extensively around the world (see "Recent ETOPS Developments").

U.S. and European manufacturers, regulatory authorities, and pilot unions continue to work together to make further changes to ETOPS requirements (see "Anticipated ETOPS Developments").

Recent ETOPS Developments
Developments in the following three areas affect operators who use extended-range twin-engine operations (ETOPS):

This method has become the most preferred means of obtaining ETOPS operational approval. Accelerated ETOPS emphasizes the process-oriented nature of ETOPS and can reduce or eliminate the need for in-service experience prior to ETOPS operations. Operators must show their respective regulatory authorities that they have all necessary ETOPS processes in place before beginning ETOPS operations.

The decision by the Canadian Government to withdraw rescue and fire service from small-capacity airports prompted operators in both Europe and North America to request guidance on RFF requirements for ETOPS en route alternates. Guidance was requested from the European Joint Aviation Authorities (JAA) and the U.S. Federal Aviation Administration (FAA), respectively. The FAA is planning to issue a policy letter that will define the RFF level required at ETOPS en route alternates as Category A, as specified in U.S. Federal Aviation Regulation 139. The FAA deems this to be equivalent to International Civil Aviation Organization fire fighting category RFF 4. In addition, the FAA will allow the use of municipal fire departments not located at the airport if their vehicles can meet the airplane with 30 minutes' notice. The JAA has amended its ETOPS information leaflet (IL20) to indicate RFF 4 as acceptable for an ETOPS-adequate airport.

The FAA and JAA have agreed upon the definition of single-engine speed for ETOPS. Operators are permitted to select any speed up to the maximum certified speed and use it for critical fuel and area-of-operations calculations. The FAA and JAA have also agreed on allowing credit for single-engine driftdown when determining the area of ETOPS operations.

Anticipated ETOPS Developments
Some of the principal changes being considered to the current extended-range twin-engine operations (ETOPS) rule are the following:

To enhance operational flexibility, the ETOPS rules published in the mid-1980s allowed for 120-min operations with the possibility of a 15 percent operational extension. When the rules were revised to include 180-min ETOPS, a similar provision permitting a 15 percent operational extension on 180 min was not included. The aviation industry is seeking a 15 percent operational extension on the 180-min rule to permit operators (and the pilot in command) further flexibility in selecting the most optimum en route alternate airports.

Using ETOPS has become a standard for many operators, and several European operators have requested the Joint Aviation Authorities ETOPS Working Group to consider revisiting the ETOPS requirements. Their intent is to retain those elements that add value to their ETOPS operations and delete what they consider unnecessary restrictions on two-engine-airplane operations.






Mohan Pandey
Regulatory Affairs and ETOPSEngineering
Boeing Commercial Airplane Group

Brian Smith
Regulatory Affairs and ETOPS Engineering
Boeing Commercial Airplane Group

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